Node:
scram switch
, Next:
scratch
, Previous:
science-fiction fandom
, Up:
= S =
scram switchn.
[from the nuclear power industry] An emergency-power-off switch (seeBig Red Switch), esp. one positioned to be easily hit by evacuating personnel. In general, this isnotsomething youfroblightly; these often initiate expensive events (such as Halon dumps) and are installed in adinosaur penfor use in case of electrical fire or in case some lucklessfield servoidshould put 120 volts across himself whileEaster egging. (See alsomolly-guard,TMRC.)
A correspondent reports a legend that "Scram" is an acronym for "Start Cutting Right Away, Man" (another less plausible variant of this legend refers to "Safety Control Rod Axe Man"; these are almost certainly bothbackronyms). The story goes that in the earliest nuclear power experiments the engineers recognized the possibility that the reactor wouldn't behave exactly as predicted by their mathematical models. Accordingly, they made sure that they had mechanisms in place that would rapidly drop the control rods back into the reactor. One mechanism took the form of `scram technicians'. These individuals stood next to the ropes or cables that raised and lowered the control rods. Equipped with axes or cable-cutters, these technicians stood ready for the (literal) `scram' command. If necessary, they would cut the cables, and gravity would expeditiously return the control rods to the reactor, thereby averting yet another kind ofcore dump.
Modern reactor control rods are held in place with claw-like devices, held closed by current. SCRAM switches are circuit breakers that immediately open the circuit to the rod arms, resulting in the rapid insertion and subsequent bottoming of the control rods.
Node:
scratch
, Next:
scratch monkey
, Previous:
scram switch
, Up:
= S =
scratch
1. [from `scratchpad'] adj. Describes a data structure or recording medium attached to a machine for testing or temporary-use purposes; one that can bescribbled on without loss. Usually in the combining forms `scratch memory', `scratch register', `scratch disk', `scratch tape', `scratch volume'. See alsoscratch monkey. 2. [primarily IBM] vt. To delete (as in a file).
Node:
scratch monkey
, Next:
scream and die
, Previous:
scratch
, Up:
= S =
scratch monkeyn.
As in "Before testing or reconfiguring, always mount ascratch monkey", a proverb used to advise caution when dealing with irreplaceable data or devices. Used to refer to any scratch volume hooked to a computer during any risky operation as a replacement for some precious resource or data that might otherwise get trashed.
This term preserves the memory of Mabel, the Swimming Wonder Monkey, star of a biological research program at the University of Toronto. Mabel was not (so the legend goes) your ordinary monkey; the university had spent years teaching her how to swim, breathing through a regulator, in order to study the effects of different gas mixtures on her physiology. Mabel suffered an untimely demise one day when aDECfield circusengineer troubleshooting a crash on the program's VAX inadvertently interfered with some custom hardware that was wired to Mabel.
It is reported that, after calming down an understandably irate customer sufficiently to ascertain the facts of the matter, a DEC troubleshooter called up thefield circusmanager responsible and asked him sweetly, "Can you swim?"
Not all the consequences to humans were so amusing; the sysop of the machine in question was nearly thrown in jail at the behest of certain cluelessdroids at the local `humane' society. The moral is clear: When in doubt, always mount a scratch monkey.
[The actual incident occured in 1979 or 1980. There is a version of this story, complete with reported dialogue between one of the project people and DEC field service, that has been circulating on Internet since 1986. It is hilarious and mythic, but gets some facts wrong. For example, it reports the machine as a PDP-11 and alleges that Mabel's demise occurred when DECPMed the machine. Earlier versions of this entry were based on that story; this one has been corrected from an interview with the hapless sysop. --ESR]
Node:
scream and die
, Next:
screaming tty
, Previous:
scratch monkey
, Up:
= S =
scream and diev.
Syn.cough and die, but connotes that an error message was printed or displayed before the program crashed.
Node:
screaming tty
, Next:
screen
, Previous:
scream and die
, Up:
= S =
screaming ttyn.
[Unix] A terminal line which spews an infinite number of random characters at the operating system. This can happen if the terminal is either disconnected or connected to a powered-off terminal but still enabled for login; misconfiguration, misimplementation, or simple bad luck can start such a terminal screaming. A screaming tty or two can seriously degrade the performance of a vanilla Unix system; the arriving "characters" are treated as userid/password pairs and tested as such. The Unix password encryption algorithm is designed to be computationally intensive in order to foil brute-force crack attacks, so although none of the logins succeeds; the overhead of rejecting them all can be substantial.
Node:
screen
, Next:
screen name
, Previous:
screaming tty
, Up:
= S =
screenn.
[Atari STdemoscene] Onedemoeffector one screenful of them. Probably comes from old Sierra-style adventures or shoot-em-ups where one travels from one place to another one screenful at a time.
Node:
screen name
, Next:
screw
, Previous:
screen
, Up:
= S =
screen namen.
Ahandlesense 1. This term has been common among users of IRC, MUDs, and commercial on-line services since the mid-1990s. Hackers recognize the term but don't generally use it.
Node:
screw
, Next:
screwage
, Previous:
screen name
, Up:
= S =
screwn.
[MIT] Alose, usually in software. Especially used for user-visible misbehavior caused by a bug or misfeature. This use has become quite widespread outside MIT.
Node:
screwage
, Next:
scribble
, Previous:
screw
, Up:
= S =
screwage/skroo'*j/ n.
Likelossagebut connotes that the failure is due to a designed-in misfeature rather than a simple inadequacy or a mere bug.
Node:
scribble
, Next:
script kiddies
, Previous:
screwage
, Up:
= S =
scribblen.
To modify a data structure in a random and unintentionally destructive way. "Bletch! Somebody's disk-compactor program went berserk and scribbled on the i-node table." "It was working fine until one of the allocation routines scribbled on low core." Synonymous withtrash; comparemung, which conveys a bit more intention, andmangle, which is more violent and final.
Node:
script kiddies
, Next:
scrog
, Previous:
scribble
, Up:
= S =
script kiddiespl.n.
1. The lowest form ofcracker; script kiddies do mischief with scripts and programs written by others, often without understanding theexploit. 2. People who cannot program, but who create tacky HTML pages by copying JavaScript routines from other tacky HTML pages. More generally, a script kiddie writes (or more likely cuts and pastes) code without either having or desiring to have a mental model of what the code does; someone who thinks of code as magical incantations and asks only "what do I need to type to make this happen?"
Node:
scrog
, Next:
scrool
, Previous:
script kiddies
, Up:
= S =
scrog/skrog/ vt.
[Bell Labs] To damage, trash, or corrupt a data structure. "The list header got scrogged." Also reported as `skrog', and ascribed to the comic strip "The Wizard of Id". Comparescag; possibly the two are related. Equivalent toscribbleormangle.
Node:
scrool
, Next:
scrozzle
, Previous:
scrog
, Up:
= S =
scrool/skrool/ n.
[from the pioneering Roundtable chat system in Houston ca. 1984; prob. originated as a typo for `scroll'] The log of old messages, available for later perusal or to help one get back in synch with the conversation. It was originally called the `scrool monster', because an early version of the roundtable software had a bug where it would dump all 8K of scrool on a user's terminal.
Node:
scrozzle
, Next:
scruffies
, Previous:
scrool
, Up:
= S =
scrozzle/skroz'l/ vt.
Used when a self-modifying code segment runs incorrectly and corrupts the running program or vital data. "The damn compiler scrozzled itself again!"
Node:
scruffies
, Next:
SCSI
, Previous:
scrozzle
, Up:
= S =
scruffiesn.
Seeneats vs. scruffies.
Node:
SCSI
, Next:
ScumOS
, Previous:
scruffies
, Up:
= S =
SCSIn.
[Small Computer System Interface] A bus-independent standard for system-level interfacing between a computer and intelligent devices. Typically annotated in literature with `sexy' (/sek'see/), `sissy' (/sis'ee/), and `scuzzy' (/skuh'zee/) as pronunciation guides -- the last being the overwhelmingly predominant form, much to the dismay of the designers and their marketing people. One can usually assume that a person who pronounces it /S-C-S-I/ is clueless.
Node:
ScumOS
, Next:
search-and-destroy mode
, Previous:
SCSI
, Up:
= S =
ScumOS/skuhm'os/ or /skuhm'O-S/ n.
Unflattering hackerism for SunOS, the BSD Unix variant supported on Sun Microsystems's Unix workstations (see alsosun-stools), and compareAIDX,Macintrash,Nominal Semidestructor,HP-SUX. Despite what this term might suggest, Sun was founded by hackers and still enjoys excellent relations with hackerdom; usage is more often in exasperation than outright loathing.
Node:
search-and-destroy mode
, Next:
second-system effect
, Previous:
ScumOS
, Up:
= S =
search-and-destroy moden.
Hackerism for a noninteractive search-and-replace facility in an editor, so called because an incautiously chosen match pattern can causeinfinitedamage.
Node:
second-system effect
, Next:
secondary damage
, Previous:
search-and-destroy mode
, Up:
= S =
second-system effectn.
(sometimes, more euphoniously, `second-system syndrome') When one is designing the successor to a relatively small, elegant, and successful system, there is a tendency to become grandiose in one's success and design anelephantinefeature-laden monstrosity. The term was first used by Fred Brooks in his classic "The Mythical Man-Month: Essays on Software Engineering" (Addison-Wesley, 1975; ISBN 0-201-00650-2). It described the jump from a set of nice, simple operating systems on the IBM 70xx series to OS/360 on the 360 series. A similar effect can also happen in an evolving system; seeBrooks's Law,creeping elegance,creeping featurism. See alsoMultics,OS/2,X,software bloat.
This version of the jargon lexicon has been described (with altogether too much truth for comfort) as an example of second-system effect run amok on jargon-1....
Node:
secondary damage
, Next:
security through obscurity
, Previous:
second-system effect
, Up:
= S =
secondary damagen.
When a fatal error occurs (esp. asegfault) the immediate cause may be that a pointer has been trashed due to a previousfandango on core. However, this fandango may have been due to anearlierfandango, so no amount of analysis will reveal (directly) how the damage occurred. "The data structure was clobbered, but it was secondary damage."
By extension, the corruption resulting from N cascaded fandangoes on core is `Nth-level damage'. There is at least one case on record in which 17 hours ofgrovelling withadbactually dug up the underlying bug behind an instance of seventh-level damage! The hacker who accomplished this near-superhuman feat was presented with an award by his fellows.
Node:
security through obscurity
, Next:
SED
, Previous:
secondary damage
, Up:
= S =
security through obscurity
(alt. `security by obscurity') A term applied by hackers to most OS vendors' favorite way of coping with security holes -- namely, ignoring them, documenting neither any known holes nor the underlying security algorithms, trusting that nobody will find out about them and that people who do find out about them won't exploit them. This "strategy" never works for long and occasionally sets the world up for debacles like theRTMworm of 1988 (seeGreat Worm), but once the brief moments of panic created by such events subside most vendors are all too willing to turn over and go back to sleep. After all, actually fixing the bugs would siphon off the resources needed to implement the next user-interface frill on marketing's wish list -- and besides, if they started fixing security bugs customers might begin toexpectit and imagine that their warranties of merchantability gave them some sort ofrightto a system with fewer holes in it than a shotgunned Swiss cheese, andthenwhere would we be?
Historical note: There are conflicting stories about the origin of this term. It has been claimed that it was first used in the Usenet newsgroup incomp.sys.apolloduring a campaign to get HP/Apollo to fix security problems in its Unix-cloneAegis/DomainOS (they didn't change a thing).ITSfans, on the other hand, say it was coined years earlier in opposition to the incredibly paranoidMulticspeople down the hall, for whom security was everything. In the ITS culture it referred to (1) the fact that by the time a tourist figured out how to make trouble he'd generally gotten over the urge to make it, because he felt part of the community; and (2) (self-mockingly) the poor coverage of the documentation and obscurity of many commands. One instance ofdeliberatesecurity through obscurity is recorded; the command to allow patching the running ITS system (escape escape control-R) echoed as $$^D. If you actually typed alt alt ^D, that set a flag that would prevent patching the system even if you later got it right.
Node:
SED
, Next:
segfault
, Previous:
security through obscurity
, Up:
= S =
SED/S-E-D/ n.
[TMRC, from `Light-Emitting Diode'] Smoke-emitting diode. Afriodethat lost the war. See alsoLER.
Node:
segfault
, Next:
seggie
, Previous:
SED
, Up:
= S =
segfaultn.,vi.
Syn.segment,segmentation fault.
Node:
seggie
, Next:
segment
, Previous:
segfault
, Up:
= S =
seggie/seg'ee/ n.
[Unix] Shorthand forsegmentation faultreported from Britain.
Node:
segment
, Next:
segmentation fault
, Previous:
seggie
, Up:
= S =
segment/seg'ment/ vi.
To experience asegmentation fault. Confusingly, this is often pronounced more like the noun `segment' than like mainstream v. segment; this is because it is actually a noun shorthand that has been verbed.